Overexpression of the urokinase receptor mRNA splice variant uPAR-del4/5 affects tumor-associated processes of breast cancer cells in vitro and in vivo

Sato, Sumito; Kopitz, Charlotte; Grismayer, Bettina; Beaufort, Nathalie; Reuning, Ute; Luther, Thomas; Kotzsch, Matthias; Krüger, Achim; Magdolen, Viktor

doi:10.1007/s10549-010-1042-5

Cited by 16 publications

(17 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Transfected cells were also characterized by immunocytofluorescence [22]. The intensity of rab31 immunocytostaining of transfected cells was in parallel with the results obtained by Western blot analysis (data not shown).…”

Section: Resultssupporting

confidence: 67%

“…One of these splice variants, uPAR-del4/5, encodes a molecular form of uPAR which lacks domain DII of uPAR and does not interact with its ligand uPA [21,22]. Quantification of mRNA levels of uPAR-del4/5 in tumor tissues revealed that higher uPAR-del4/5 expression - similar to rab31 - is associated with shorter disease-free survival of breast cancer patients [15,21,49].…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Rab31 expression levels modulate tumor-relevant characteristics of breast cancer cells

et al. 2012

Self Cite

View full text Add to dashboard Cite

BackgroundRab proteins constitute a large family of monomeric GTP-binding proteins that regulate intracellular vesicle transport. Several Rab proteins, including rab31, have been shown to affect cancer progression and are related with prognosis in various types of cancer including breast cancer. Recently, the gene encoding rab31 was found to be overexpressed in estrogen receptor-positive breast cancer tissue. In a previous study we found a significant association of high rab31 mRNA expression with poor prognosis in node-negative breast cancer patients. In the present study, we aimed to investigate the impact of rab31 (over)-expression on important aspects of tumor progression in vitro and in vivo.MethodsBreast cancer cells displaying low (MDA-MB-231) or no (CAMA-1) endogenous rab31 expression were stably transfected with a rab31 expression plasmid. Batch-transfected cells as well as selected cell clones, expressing different levels of rab31 protein, were analyzed with regard to proliferation, cell adhesion, the invasive capacity of tumor cells, and in vivo in a xenograft tumor model. Polyclonal antibodies directed to recombinantly expressed rab31 were generated and protein expression analyzed by immunohistochemistry, Western blot analysis, and a newly developed sensitive ELISA.ResultsElevated rab31 protein levels were associated with enhanced proliferation of breast cancer cells. Interestingly, weak to moderate overexpression of rab31 in cell lines with no detectable endogenous rab31 expression was already sufficient to elicit distinct effects on cell proliferation. By contrast, increased expression of rab31 in breast cancer cells led to reduced adhesion towards several extracellular matrix proteins and decreased invasive capacity through MatrigelTM. Again, the rab31-mediated effects on cell adhesion and invasion were dose-dependent. Finally, in a xenograft mouse model, we observed a significantly impaired metastatic dissemination of rab31 overexpressing MDA-MB-231 breast cancer cells to the lung.ConclusionsOverexpression of rab31 in breast cancer cells leads to a switch from an invasive to a proliferative phenotype as indicated by an increased cell proliferation, reduced adhesion and invasion in vitro, and a reduced capacity to form lung metastases in vivo.

show abstract

Section: Resultssupporting

confidence: 67%

Section: Discussionmentioning

confidence: 99%

Rab31 expression levels modulate tumor-relevant characteristics of breast cancer cells

et al. 2012

Self Cite

View full text Add to dashboard Cite

show abstract

“…24,26 This truncated receptor may, nevertheless, still be GPI-anchored on the cell surface as the signal peptide and the GPI anchorage site remain intact. 27,28 At present, however, it remains to be proven whether this variant is expressed in vivo at the protein level and is secreted in detectable amounts into the circulation.…”

Section: Discussionmentioning

confidence: 99%

Administration of Recombinant Soluble Urokinase Receptor Per Se Is Not Sufficient to Induce Podocyte Alterations and Proteinuria in Mice

Cathelin

Placier

Ploug

et al. 2014

Journal of the American Society of Nephrology

View full text Add to dashboard Cite

Circulating levels of soluble forms of urokinase-type plasminogen activator receptor (suPAR) are generally elevated in sera from children and adults with FSGS compared with levels in healthy persons or those with other types of kidney disease. In mice lacking the gene encoding uPAR, forced increases in suPAR concentration result in FSGS-like glomerular lesions and proteinuria. However, whether overexpression of suPAR, per se, contributes to the pathogenesis of FSGS in humans remains controversial. We conducted an independent set of animal experiments in which two different and well characterized forms of recombinant suPAR produced by eukaryotic cells were administered over the short or long term to wild-type (WT) mice. In accordance with the previous study, the delivered suPARs are deposited in the glomeruli. However, such deposition of either form of suPAR in the kidney did not result in increased glomerular proteinuria or altered podocyte architecture. Our findings suggest that glomerular deposits of suPAR caused by elevated plasma levels are not sufficient to engender albuminuria.

show abstract

“…Whereas wild-type uPAR consists of three structurally homologous domains, in the uPAR-del4/5 variant the complete domain II of uPAR is deleted, and the uPAR-del4/5 protein does not interact with either of its ligands uPA or vitronectin [17]. However, in breast cancer cells the overexpression of the uPAR-del4/5 protein profoundly affects the in vitro invasion capacity of cells through a Matrigel matrix, the adhesion to extracellular matrix proteins and also lung colonization in an in vivo metastasis model.…”

Section: Introductionmentioning

confidence: 99%

Combined mRNA expression levels of members of the urokinase plasminogen activator (uPA) system correlate with disease-associated survival of soft-tissue sarcoma patients

et al. 2011

Self Cite

View full text Add to dashboard Cite

BackgroundMembers of the urokinase-type plasminogen activator (uPA) system are up-regulated in various solid malignant tumors. High antigen levels of uPA, its inhibitor PAI-1 and its receptor uPAR have recently been shown to be associated with poor prognosis in soft-tissue sarcoma (STS) patients. However, the mRNA expression of uPA system components has not yet been comprehensively investigated in STS patients.MethodsThe mRNA expression level of uPA, PAI-1, uPAR and an uPAR splice variant, uPAR-del4/5, was analyzed in tumor tissue from 78 STS patients by quantitative PCR.ResultsElevated mRNA expression levels of PAI-1 and uPAR-del4/5 were significantly associated with clinical parameters such as histological subtype (P = 0.037 and P < 0.001, respectively) and higher tumor grade (P = 0.017 and P = 0.003, respectively). In addition, high uPAR-del4/5 mRNA values were significantly related to higher tumor stage of STS patients (P = 0.031). On the other hand, mRNA expression of uPA system components was not significantly associated with patients' survival. However, in STS patients with complete tumor resection (R0), high PAI-1 and uPAR-del4/5 mRNA levels were associated with a distinctly increased risk of tumor-related death (RR = 6.55, P = 0.054 and RR = 6.00, P = 0.088, respectively). Strikingly, R0 patients with both high PAI-1 and uPAR-del4/5 mRNA expression levels showed a significant, 19-fold increased risk of tumor-related death (P = 0.044) compared to the low expression group.ConclusionOur results suggest that PAI-1 and uPAR-del4/5 mRNA levels may add prognostic information in STS patients with R0 status and distinguish a subgroup of R0 patients with low PAI-1 and/or low uPAR-del4/5 values who have a better outcome compared to patients with high marker levels.

show abstract

Overexpression of the urokinase receptor mRNA splice variant uPAR-del4/5 affects tumor-associated processes of breast cancer cells in vitro and in vivo

Abstract: Conclusions: We demonstrate that the uPAR-del4/5 mRNA splice variant mediates tumorrelevant biological processes in vitro and in vivo. Our results thus illustrate how tumorspecific alternative splicing can distinctly impact the biology of the tumor.

Cited by 16 publications

References 32 publications

Rab31 expression levels modulate tumor-relevant characteristics of breast cancer cells

Rab31 expression levels modulate tumor-relevant characteristics of breast cancer cells

Administration of Recombinant Soluble Urokinase Receptor Per Se Is Not Sufficient to Induce Podocyte Alterations and Proteinuria in Mice

Combined mRNA expression levels of members of the urokinase plasminogen activator (uPA) system correlate with disease-associated survival of soft-tissue sarcoma patients

Contact Info

Product

Resources

About